Mizoram is a hilly state of North-east India with a tropical and subtropical climate which falls under sub-region III of Eastern Himalayan Zone II of India, according to agro-climate division. The average rainfall of the state is about 350° 8 cm per annum with a temperature ranging from 10°C to 21 °C in winter and 20°C to 29°C in summer, unlike other states of India. Not much is known on prevalence of parasites and parasitic diseases of animals from this state. Earlier reports from north-east are mainly based on study carried out in Assam and Meghalaya (Endrejat, 1964; Miranpuri and Lahkar, 1979; Baruah and Gogoi, 1989; Deka et al., 1985; Deka et al., 1995; Borthakur and Das, 1998; Roy and Tandon, 1992). From the state of Mizoram, Zakhuma (1998) reported a case of “surra” in Champhai district on the border of Burma. Thereafter, no published data on parasites are available. The present communication reports the occurrence of endo and ecto parasites in different animals in this hilly region.

The present investigation was limited to Aizawl and adjoining villages from March 2001 to August 2002. The study included the examination of carcasses in unorganized and private abattoirs at Durtlang, Selesih, Sihphir and Aizawl besides the necropsies conducted in the Parasitology Department of this Central Agricultural University. Carcass of 138 pigs, 102 cattle, 34 dogs and 57 birds were examined during the study. Faecel samples and skin scrapings were examined using routine parasitological methods (Soulsby, 1982). Arthropod specimens were identified according to Sen and Fletcher (1962).

Examination of 351 faecal samples and 274 carcasses of animals revealed an overall parasitic infections of 25.64% and 21.89%, respectively. Amongst helminths, nematode infection accounted for higher prevalence in all species of animals examined followed by cestode infection (Table 1). No trematode ova could be recorded in any of the species during faecal examination but a low level of trematode infection in cattle (6.82%) was encountered in abattoir survey. Arthropods and protozoan infections were recorded at 16.38% and 22.4%, respectively.

In cattle, among the nematode infections (14.45%) recorded, Nematodirrns fillicolis, Haemonchus contortus Trichostrongylus, spp., Oesophagostomum raditum and Toxocara vitulorum were common. Larval cestodes, Cysticercus tenuicollis and hydatid cysts were also encountered. Of the ectoparasites, Haematopinus tuberculatus, Linognathus vituli, Rhipicephalus sanguineus, Boophilus microplus and Sarcoptes scabei were common. Although, no haemoprotozoan infection from the study area was recovered but enteric coccidia viz., Eimeria bovis in cattle and E. acervulina in poultry were recorded.

The overall infection of pigs was 23.79%, of which nematode infection accounted for 19.21 % and Ascaris suum was the predominant species among nematodes. Heavy burden of Balantidium coli infection was also recorded in pigs.

In dogs, nematode infections were higher (30.76%) than cestode infections (29.41%). Among the cestodes, Diphylobotrium latum and Dipylidium caninuum were important and Ancyclostoma caninum, Toxocara canis and Dirofilaria immitis were the common nematodes.

An overall prevalence of 36.84% helminthic infections in birds were recorded of which Ascaridia galli, Raillientina tetragona and Raillietina echinobothridia were the predominant species.

During the course of study, faecal examination of 1 horse, 14 cats and 10 goats in the vicinity showed the presence of strongyle infection. Toxocara cati was predominant in cat and Haemonchus and Oesophagustomum species in goats.

The present findings differ from the previous reports of N.E. region. In cattle, prevalence of strongyle infection was low. The low prevalence of strongyle infection might be due to the hilly rearing and management practices followed in this part of the country. Dairy cows in Mizoram are generally stall-fed on wooden floor in the slopes of hills and the green plants and leaves are fed to animals in bunch. Absence of contaminated pastures may be explained with low prevalence of strongyle infection. The frequent occurrence of T. vitulorium in calves might be due to prenatal transmission. Absence of snail intermediate hosts in this hilly area may be a key factor for low trematode infection in local cattle of Mizoram. However, at slaughter trematode infection (6.86%) viz., Paramphistomum sp. and Fasciola sp. were recorded, however, it does not reflect the true incidence from this area as the slaughtered animals examined are brought from adjoining states of Assam or Myanmar. Most of the research data generated on the occurrence of Fasciola gigantica infection is based on abattoir surveys and faecal examination of fluke eggs which are biased (Sanyal, 2001).

The common occurrence of dog flea (C. canis) is related to D. caninum infection but the frequency of D. latum infection in fact requires a thorough investigation.

Ascaris suum and B. coli were highly common in pigs. Rajkhowa (1996) reported that A. suum infection was highest (69.3%) in young pigs from Meghalaya. The ixodid ticks, Boophilus sp., Rhipicephalus sp., Haemophysalis sp. ticks have a linear relationship with microclimate, quantity of herbage, temperature, humidity, rainfall, etc. No haemoprotozoan infection could be recorded but it requires further study as arthropod vectors in this part of country.

It can be concluded from this preliminary study that parasitosis in animals in Aizawl district of Mizoram, assumes a low profile.

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